The Design And Application Of New Semiautomatic Biochemistry Analyzer

Biochemistry analyser is frequently used in the clinical testing of humanbody fluids in a variety of substances, such as blood sugar, blood lipid,inorganic ions, serum enzymes,hepatic function, protein and non-nitrogencompounds and other types of conventional biochemical index. Because ofthe lag in the development experience and the overall level of domesticprocessing industries backward, automatic biochemical analyser productiontechnologies are dominated by Japan, the United States, Italy and othermedical equipment manufacturers. The domestic producers can't producesteady-going automatic biochemical analyser, production processes requireonly relatively simple semi-automatic biochemical analyser. Along with thethe improving of the health care system,The demands of small and mediumcommunity hospitals to semi-automatic biochemical analyser and smallautomatic biochemical analyser increased every year, which provide a newsubject to domestic medical equipment manufacturers --suitable for thedevelopment of domestic markets semi-automatic biochemical analyserproducts, and gradually develop our own intellectual property rights ofautomatic biochemical analyser products.General in biochemical analyser test process, firstly, use biochemicalreactions Hin color response to statistical samples in a particular wavelengthsolution with the greatest absorption peak, and then use ultraviolet and visiblespectroscopic measurements to test the absorbency of material to the specificwavelength, the final adoption of Bill Law to calculate the correspondingmaterial concentrations. Specific measurement methods are : 1. Absorbencymethods, 2. Endpoint methods, 3. Kinetics methods , In order to improvethe speed of the measurement, complete the double wavelength analyticalmethods, improving measurement accuracy and based the technologygroundwork for the future development of a automatic biochemical analyser,we designed a new type of semi-automatic biochemical analyser. For theinstruments mainly face to the domestic markets, we use a high-pixels colourLCD screen and increased Chinese operational interface and the output ofresult. And we produced a separate Chinese characters library for allowingusers to input the codes to obtain the corresponding Chinese character. Tofacilitate the users' use, the equipment provided 36 pre-stored programme forthe measurement project and up to 200 users own programme for themeasurement project. So we need greater storage space (128KB of ROM)and user data storage space (EEPROM). The 51 single-chip microcontrolleronly have 16 addresses lines, which meant that its most code space is 64KB.In order to get more code space, we use the Code banking function in Keil C,This function enable the 51 single-chip microcontroller can manage a seriesof 51 regional public and 64 pieces of 64KB-ROM chips at the largest(7.09version), thus the maximum achievable 4MB code space, which will meet theprocedures we use more storage space requirements. To improve themeasurement of the speed of the equipment, we increased the clockfrequency of ad-changer chip, and designed separate logarithm hardwarecircuit with temperature compensation function. To improve the measurement,we also designed a separate wisdom temperature control system based on 51single-chip microcontroller. We input the temperature sensors error curve inadvance,and then compensate the result. At the same time, through the use ofPID control methods to control PWM wave driven H bridge circuit withstable response room temperature. The system ensures temperature stabilityand the enhanced the accuracy of the kinetics method's results.Software respect, in order to improve the development efficiency andcommonability of the procedure, taking into account operational efficiencyprocedures, we used the C language and the assembly language mixedpreparation. Such as operation and the printing interface pictures and dataprocessing we used C languages, and hardware operations against somebottom module we used assembly languages. This is a better way to use themathematical function of the C language to deal with float point data, and touse assembly language's flexible enhanced procedures to run efficiently. Butat the same time this method bring us a problem which we must enable Clanguage use assembly language, for which we introduced a Keil C providedmethod, with which we can easily write a function with assembly language,which can be recognised by C language.The Kinetics method's results, we applied the linear fit Leastsquares-methods, the use of the C language float point data function,allowing the development of greatly improving the efficiency, accuracy anddata processing than previously used assembly language to developprocedures to add one bit valid figure.Through the above improvements, the current equipment will completea sample point measurements in about 0.2 seconds, and has successfullyachieved double wavelength analytical method. For those who turbidity, theeffect of prone scattering samples double wavelength analytical methodmeasurement's error than the older machines, single-wavelengthmeasurements of the average reduced by 7.5% deviation measurements,increased sensitivity and anti-jamming capabilities.The above improvement of light way, circuit, is good for the high speedand large number measures, press close to the technical requirement for theautomatic biochemical analysis instrument further, all these haveaccumulated essential technological experience for research and developmentof the automatic biochemical analysis instrument in the future.